Balance spring mechanism



Nov. 24, 1964 L. E. PETERS BALANCE SPRING MECHANISM 2 Sheets-Sheet 1 Filed Sept. 20. 1962 Ill!illlllliiiiiiiililll INVENTOR LOWELL E. PETERS WOOQ, HERRON 8| EVANS ATTORNEYS Nov. 24, 1964 E. PETERS BALANCESPRING MECHANISM 2 Sheets-Sheet 2 Filed Sept. 20, 1962 paw Juan INVENTOR. LOWE-LL E. PETERS WOOD, HERRON 8 EVANS ATTORNEYS United States Patent 3,157,917 BALANCE SPRING MECHANISM Lowell E. Peters, 2386 Grandin Road, Cincinnati, Ohio Filed Sept. 20, 1962, Ser. No. 225,091 Claims. (Cl. 20-42) This invention relates to tilt-out windows of the type described in my copending applications Serial No. 113,216, filed May 29, 1961, now Patent No 3,055,062, and Serial No. 115,717, filed June 8, 1961, and now Patent No. 3,055,063, both patents granted September 25, 1962.

The tilt-out windows of the type disclosedin these applications comprise at least one vertically slidable window sash secured at its lower corners to balance springs which are mounted in side jamb weather stripping with their upper ends secured to the side jamb weather stripping. The connection between the lower ends of the balance springs and the sash is by means of a lock mechanism which has not only the function of connecting the balance spring to the sash, but additionally locks the balance springs in a downwardly extended, stressed condition when the sash has been tilted out and removed. By maintaining the balance springs in the extended position during removal of the sash, the return of the sash to its proper position in the jamb with lower corners connected to the balance springs is easily eifected.

From time to time the sash might be improperly removed so that the lock is not fully effective or the lock might inadvertently be tripped when the sash is removed. Under such conditions the energy of the stressesd spring quickly snaps the spring upwardly to its unstressed position against the screw or other means by which the upper end of the spring is secured in the side jamb. Because the spring is lightweight, it would appear that the impact of the spring against its mounting would cause no problem other than the awkwardness of bringing the spring once again to a lower position to permit the return of the sash to its proper position in the side jamb. However, I have found that repeated upward snapping of the spring against its mounting causes a progressive permanent deformation in the spring which results in a loss of the originally designed spring characteristics. Such repeated abuse of the spring gives rise to a loss of effectiveness of the spring over a short period of time. As few as four or five impacts of the spring against its mounting will cause such deformation of the spring as to reduce the efiectiveness of the spring to the point of uselessness.

It has been an objective of'the invention to provide a balance spring mounting which eliminates the deleterious effects of the impact of the spring upon it. To this end I provide a resilient bumper or shock absorber secured in a side jamb immediately adjacent the upper end of the balance spring. Preferably the shock absorber is a soft rubber block which has a degree of resilience suflicient to absorb so much of the shock energy as is necessary to avoid the permanent deformation of the metal of the balance spring.

More specifically, the balance spring is formed as a helix and is provided a vertically projecting loop at one end through which a mounting screw passes. The shock absorber is an elongated block having a transverse bore at its lower end through which the mounting screw may pass. When in proper position the mounting loop of the balance spring passes above the lower end of the shock absorber block and brings the first coil of the balance spring helix immediately adjacent the lower surface of the block. I have found that a solid rubber block having no bore in the lower end thereof is markedly less eifective in absorbing the impact of the balance spring than the preferred block of the invention which has the bore in the lower end. Perhaps the bore in the lower end of the block permits the block to flex to a greater extent upon impact, thereby absorbing a greater portion of the energy of the impacting balance spring.

It has been another objective of the invention to provide for the absorption of at least a portion of the balance spring noise attending the normal raising and lowering of the window sash. By providing a resilient block which snugly engages the side jamb weather stripping and which is immediately adjacent one end of the balance spring, the noise developed by the operation of the balance spring is markedly reduced.

These and other objects of the invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of a tilt-out window of the type with which my invention is employed;

FIG. 2 is a fragmentary perspective view of a window showing my invention;

FIG. 3 is an elevational view of the balance spring mounting;

FIG. 4 is a cross-sectional view taken along lines 44 of FIG. 3; and,

FIG. 5 is a cross-sectional view taken along lines 5--5 of FIG. 3.

Referring to FIG. 1, the window indicated at 10 includes an upper sash 11 and a lower sash 12 which are normally slidably mounted to side jamb weather stripping 13 on each side of the window frame. The side jamb weather stripping may be an extruded aluminum section having the configuration best illustrated in FIG. 5, the weather stripping being spring biased toward the sash by springs 14. The side jamb weather stripping has two longitudinal grooves 15 which slidably receive the sash side stiles and maintain them in proper position in the window frame during normal usage. When it is desired to tilt the sash to the positions shown in FIG. 1, the top rail of each sash is grasped and pulled inwardly whereupon the side jamb weather stripping is forced away from the sash against the action of springs 14 to permit the sash to be swung inwardly.

The lower corners of each sash are provided with slots 17 to receive pins 18 forming a part of the lock mechanism by which the sash are secured to the balance springs. As described in my earlier applications referred to above, when the pins 18 are in a normal position, the lock mechanism is free to slide within the weather stripping, but when the pins are pivoted through an angle of a lock is effected between the look mechanism and the weather stripping to hold the lock mechanism in a lower position against the urging of the stressed balance spring.

It should be understood that the particular configuration of the side jamb and the particular operation and form of the lock mechanism do not form a part of the present invention, but are merely described as illustrative of one form of mounting the window sash and securing them to their respective balance springs.

As best shown in FIG. 2, the lock mechanism indicated at 19 is fixed to the lower end 20 of a balance spring 21. The upper end 22 of the balance spring is fixed by a screw 23 to the side jamb, the screw passing through a hole 24 in the side jamb weather stripping and being screwed as at 25 into the wood frame of the window. The upper end 22 of the balance spring 21 has a vertically projecting loop 26 through which the screw passes and by which the balance spring is fixed at its upper end.

The balance spring and lock mechanism are disposed in a channel 28 formed in the side jamb weather stripping.

At the upper end of the channel 28 a resilient block 29 forming a shock absorber is fixedly mounted. The block 29 has an external configuration matching the internal configuration of the channel 28 so that it is snugly lodged in the channel. The lower end of the block has a bore 30 overlying the screw 23 and through which the screw 23 may pass during the mounting of the balance spring in the assembly.

The projecting of the loop 26 of the balance spring above the lower surface 31 of the block 29 brings the uppermost coil 32 immediately adjacent the lower surface 31 of the block. Thus, there is assurance that upon inadvertent release of the lock mechanism 19 the energy of the impacting spring will be transmitted directly to the resilient block 29, rather than to any rigid portion of the sash mounting.

In the operation of the invention, the sash are normally vertically disposed and are slidable in a vertical direction within the grooves 15 of the side jamb weather stripping. The balance springs offset the force of gravity on the sash and facilitate the raising and lowering of the sash. During such raising and lowering of the sash, a substantial portion of the noise generated by the balance springs is absorbed in the resilient block 29. From time to time it may be desired to remove the sash as for washing. On such occasions the upper rails of the sash are pulled inwardly causing the sash to tilt about the pins 18. Prior to or during this operation the lock mechanism 19 is fixed to the side jamb weather stripping in order to maintain the balance springs in an extended condition. It is desirable that the balance springs be maintained in an extended position so that the sash may conveniently be returned to their proper position of engagement with the pins 18.

If for some reason the lock mechanism fails to hold, as by being inadvertently tripped or the like, the energy stored in the spring will be released to drive the spring sharply upwardly into impact with the shock absorbing block 29. The kinetic energy of the impacting spring will be substantially entirely absorbed by the resilient block in such a manner as to prevent the permanent deformation of the spring metal. Thus, the desired spring characteristics of the balance springs will be retained even through an extruded number of impacts of the spring against the mounting at its upper end.

I claim:

1. Balance mechanism for a tilt out window comprising,

a side jamb for slidably receiving window sash,

a balance spring fixed at an upper end to said side jamb,

and a resilient block secured to said side jamb immediately adjacent the upper end of said spring and engageable by said spring.

2. Balance mechanism for tilt out window comprising,

a side jamb for slidably receiving window sash,

a balance spring fixed at an upper end to said side jamb,

a balance spring lock slidably mounted in said side jamb and fixed to the lower end of said balance spring, i i

and a resilient block secured to said side jamb immediately adjacent the upper end of said spring and engageable by said spring.

3. Balance mechanism for a tilt out window comprising,

a side jamb weather stripping for slidably receiving window sash,

said weather stripping having an elongated rectangular channel,

a balance spring disposed in said channel and fixed at an upper end to said weather stripping,

a balance spring lock slidably mounted in said channel and fixed to the lower end of said balance spring, and a resilient bumper having a transverse configuration conforming to the transverse configuration of said channel said bumper being seated in the upper end of said channel with its lower surface immediately adjacent the upper end of said spring and engageable by said spring.

4. Balance mechanism for a tilt out window comprising,

a side jamb for slidably receiving window sash,

a balance spring,

a screw secured in said side jamb,

said balance spring having a vertically projecting loop secured to said screw to fix the upper end of said balance spring to said side jamb,

a balance spring lock slidably mounted in said side jamb and fixed to the lower end of said balance spring,

and a resilient bumper secured to said side jamb immediately adjacent the upper end of said spring,

said resilient bumper having a lower surface extending below said vertically projecting loop of said balance spring, said lower surface being engageable by said spring.

5. Balance mechanism for a tilt out window com- PFlSlIlg,

a side jamb for slidably receiving window sash,

a balance spring fixed by a screw at an upper end to said side jamb,

a balance spring lock slidably mounted in said side jamb and fixed to the lower end of said balance spring,

and a resilient bumper secured to said side jamb immediately adjacent the upper end of said spring, and engageable by said spring,

said bumper having a transverse bore adjacent the lower end thereof and normally overlying said screw to provide access thereto.

References Cited in the file of this patent UNITED STATES PATENTS 

1. BALANCE MECHANISM FOR A TILT OUT WINDOW COMPRISING, A SIDE JAMB FOR SLIDABLY RECEIVING WINDOW SASH, A BALANCE SPRING FIXED AT AN UPPER END TO SAID SIDE JAMB, AND A RESILIENT BLOCK SECURED TO SAID SIDE JAMB IMMEDIATELY ADJACENT THE UPPER END OF SAID SPRING AND ENGAGEABLE BY SAID SPRING. 